The invention concerns a method for extending a visibility area obtained by means of a camera mounted on a vehicle, in particular on a motor vehicle.
In particular, the field of the invention comprises visual reversing aid (VRA) systems, using one or more cameras. The aim of such systems is to assist the driver during low-speed manoeuvres, displaying for him an intuitive visual representation of the near environment around the vehicle.
EP1094337 discloses a system intended to assist a driver during a parking manoeuvre, warning him of the presence of a three-dimensional object detected by means of a single image acquisition apparatus. The disclosed system has the aim of determining the distance which separates the object from the vehicle from two successive image acquisitions which are used to create a stereoscopic view as a function of the displacement of the vehicle calculated from sensors.
This type of embodiment requires a very high precision of the sensors. Furthermore, on movements at low speed as is generally the case during a manoeuvre, the small distance covered by the vehicle between two image acquisitions poses difficulties for a three-dimensional image reconstruction, because this is equivalent to a stereoscopic system having a very short base. Jumping images until a sufficient covered distance is obtained poses the problem of the dynamics of the environment. An object in movement in the scene can not be reconstructed. A sufficiently precise reconstruction of the obstacles requires a costly calculation power. Last and not least of the disadvantages, only the objects which are in the field of the camera during the two successive image acquisitions can be reconstructed.